A novice golfer on the green takes three strokes to sink the ball. The successive displacements are 4.00 m to the north, 2.00 m northeast, and 1.00 m at 30.0 degrees west of south. Starting at the same initial point, an expert golfer could make the hole in what single displacement?
What confuses me is how to visualize the problem, and how to go about it.
(There'll be more than one problem)
------- A well a bird bird bird! The bird is the word!
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kobe24gk
Technician
just draw it....a line up then a line northeast etc...then from the starting point draw a straight line to the ending point..use triangles etc to find the displacement
you know the angle at the point where the 4 line meets the 2 line...because the NW 2m line will go at 45, so the obtuse angle will be 90+45=135. Then you know the other two angles too (hint: 45-30).
Your answer is the length of the missing piece of the third side. So figure out what the full length is of that side (by using that triangle), then subtract 1m from it to get the size of the gap.
Post edited at 9:05 pm on Dec. 1, 2008 by LittleNutTammi
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you know the angle at the point where the 4 line meets the 2 line...because the NW 2m line will go at 45, so the obtuse angle will be 90+45=135. Then you know the other two angles too (hint: 45-30).
Your answer is the length of the missing piece of the third side. So figure out what the full length is of that side (by using that triangle), then subtract 1m from it to get the size of the gap.
Using the law of cosines, right? I got 4.67 as an answer, but my book says it's 4.64. I dunno. It also has an angle measured, which I don't know how to get, except that it involves tan^-1.
------- A well a bird bird bird! The bird is the word!
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you know the angle at the point where the 4 line meets the 2 line...because the NW 2m line will go at 45, so the obtuse angle will be 90+45=135. Then you know the other two angles too (hint: 45-30). 
